13,053 results match your criteria Biotechnology and bioengineering[Journal]


Adipose-derived stem cell-derived Extracellular Matrix represents a promising Biomaterial by inducing spontaneous formation of Prevascular-like Structures by MvECs.

Biotechnol Bioeng 2020 Jul 3. Epub 2020 Jul 3.

Reutlingen University, School of Applied Chemistry, Reutlingen, Germany.

Tissue constructs of physiologically relevant scale require a vascular system to maintain cell viability. However, in vitro vascularization of engineered tissues is still a major challenge. Successful approaches are based on a feeder layer (FL) to support vascularization. Read More

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http://dx.doi.org/10.1002/bit.27481DOI Listing

Biomass and Pigment Production for Arthrospira platensis via Semi-Continuous Cultivation in Photobioreactors: Temperature Effects.

Biotechnol Bioeng 2020 Jun 29. Epub 2020 Jun 29.

School of Chemical and Biomolecular Engineering, Georgia Institute of Technology Atlanta, GA, 30332.

This study describes the response of Arthrospira platensis to a variety of temperature conditions as reflected in variations of photosynthetic parameters, pigmentation, and biomass productivity in indoor photobioreactor (PBR) cultivations. These experiments are designed to better understand the impact of temperature, seasonal variations, and acclimation effects on outdoor biomass production. The irradiance level and temperature range (20 - 39°C) are chosen to enable modeling of semi-continuous operation of large-scale outdoor PBR deployments. Read More

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http://dx.doi.org/10.1002/bit.27480DOI Listing

Techno-economic analysis of semicontinuous bioreactor production of biopharmaceuticals in transgenic rice cell suspension cultures.

Biotechnol Bioeng 2020 Jun 27. Epub 2020 Jun 27.

Department of Chemical Engineering, University of California, Davis, CA, USA.

Biopharmaceutical protein production using transgenic plant cell bioreactor processes offers advantages over microbial and mammalian cell culture platforms in its ability to produce complex biologics with simple chemically-defined media and reduced biosafety concerns. A disadvantage of plant cells from a traditional batch bioprocessing perspective is their slow growth rate which has motivated us to develop semicontinuous and/or perfusion processes. Although the economic benefits of plant cell culture bioprocesses are often mentioned in the literature, to our knowledge no rigorous techno-economic models or analyses have been published. Read More

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http://dx.doi.org/10.1002/bit.27475DOI Listing

Efficient secretory production of large-size heterologous enzymes in Bacillus subtilis: a secretory partner and directed evolution.

Biotechnol Bioeng 2020 Jun 26. Epub 2020 Jun 26.

Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, 32 West 7th Avenue, Tianjin Airport Economic Area, Tianjin, 300308, China.

Secretory production of recombinant proteins provides a simple approach of the production and purification of target proteins in the enzyme industry. We developed a combined strategy for the secretory production of three large-size heterologous enzymes with a special focus on 83-kDa isoamylase (IA) from an archaeon Sulfolobus tokodaii in a bacterium Bacillus subtilis. First, a secretory protein of the B. Read More

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http://dx.doi.org/10.1002/bit.27478DOI Listing

Immobilization rapidly selects for chemoresistant ovarian cancer cells with enhanced ability to enter dormancy.

Biotechnol Bioeng 2020 Jun 26. Epub 2020 Jun 26.

Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, MN, 55455, USA.

Around 20-30% of ovarian cancer patients exhibit chemoresistance, but there are currently no methods to predict whether a patient will respond to chemotherapy. Here, we discovered that chemoresistant ovarian cancer cells exhibit enhanced survival in a quiescent state upon experiencing the stress of physical confinement. When immobilized in stiff silica gels, most ovarian cancer cells die within days, but surviving cells exhibit hallmarks of single cell dormancy. Read More

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http://dx.doi.org/10.1002/bit.27479DOI Listing

Human Trabecular Meshwork Cell Behavior is Influenced by Collagen Scaffold Pore Architecture and Glycosaminoglycan Composition.

Biotechnol Bioeng 2020 Jun 26. Epub 2020 Jun 26.

University of Colorado School of Medicine, Department of Ophthalmology, 1675 Aurora Ct., Aurora, CO, 80045.

Glaucoma is a degenerative eye disease in which damage to the optic nerve leads to a characteristic loss of vision. The primary risk factor for glaucoma is increased intraocular pressure which is caused by an imbalance of aqueous humor generation and subsequent drainage through the trabecular meshwork (TM) drainage system. The small size, donor tissue limitations, and high complexity of the TM makes it difficult to research the relationship between the TM cells and their immediate environment. Read More

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http://dx.doi.org/10.1002/bit.27477DOI Listing

Aggregation-induced integrated stress response rejuvenates culture-expanded human mesenchymal stem cells.

Biotechnol Bioeng 2020 Jun 24. Epub 2020 Jun 24.

Department of Chemical and Biomedical Engineering, FAMU-FSU College of Engineering, Florida State University, Tallahassee, Florida.

Protein homeostasis is critical for cellular function, as loss of homeostasis is attributed to aging and the accumulation of unwanted proteins. Human mesenchymal stem cells (MSCs) have shown promising therapeutic potential due to their impressive abilities to secrete inflammatory modulators, angiogenic, and regenerative cytokines. However, there exists the problem of human MSC expansion with compromised therapeutic quality. Read More

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http://dx.doi.org/10.1002/bit.27474DOI Listing
June 2020
4.126 Impact Factor

Increased metal tolerance and bioaccumulation of zinc and cadmium in Chlamydomonas reinhardtii expressing a AtHMA4 C-terminal domain protein.

Biotechnol Bioeng 2020 Jun 24. Epub 2020 Jun 24.

Department of Earth and Environmental Sciences, School of Natural Sciences, The University of Manchester, Manchester, UK.

The use of microalgal biomass for metal pollutant bioremediation might be improved by genetic engineering to modify the selectivity or capacity of metal biosorption. A plant cadmium (Cd) and zinc (Zn) transporter (AtHMA4) was used as a transgene to increase the ability of Chlamydomonas reinhardtii to tolerate 0.2 mM Cd and 0. Read More

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http://dx.doi.org/10.1002/bit.27476DOI Listing

On the donor substrate dependence of group transfer reactions by hydrolytic enzymes: insight from kinetic analysis of sucrose phosphorylase-catalyzed transglycosylation.

Biotechnol Bioeng 2020 Jun 23. Epub 2020 Jun 23.

Institute of Biotechnology and Biochemical Engineering, Graz University of Technology, NAWI Graz, Petersgasse 10-12/I, A-8010, Graz, Austria.

Chemical group-transfer reactions by hydrolytic enzymes have considerable importance in biocatalytic synthesis and are exploited broadly in commercial-scale chemical production. Mechanistically, these reactions have in common the involvement of a covalent enzyme intermediate which is formed upon enzyme reaction with the donor substrate and is subsequently intercepted by a suitable acceptor. Here, we studied the glycosylation of glycerol from sucrose by sucrose phosphorylase (SucP) to clarify a peculiar, yet generally important characteristic of this reaction: partitioning between glycosylation of glycerol and hydrolysis depends on the type and the concentration of the donor substrate used (here: sucrose, α-D-glucose 1-phosphate (G1P)). Read More

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http://dx.doi.org/10.1002/bit.27471DOI Listing

Carbohydrate-binding domains facilitate efficient oligosaccharides synthesis by enhancing mutant catalytic domain transglycosylation activity.

Biotechnol Bioeng 2020 Jun 23. Epub 2020 Jun 23.

Department of Chemical and Biochemical Engineering, Rutgers, The State University of New Jersey, Piscataway, New Jersey.

Chemoenzymatic approaches using carbohydrate-active enzymes (CAZymes) offer a promising avenue for the synthesis of glycans like oligosaccharides. Here, we report a novel chemoenzymatic route for cellodextrins synthesis employed by chimeric CAZymes, akin to native glycosyltransferases, involving the unprecedented participation of a "non-catalytic" lectin-like domain or carbohydrate-binding modules (CBMs) in the catalytic step for glycosidic bond synthesis using β-cellobiosyl donor sugars as activated substrates. CBMs are often thought to play a passive substrate targeting role in enzymatic glycosylation reactions mostly via overcoming substrate diffusion limitations for tethered catalytic domains (CDs) but are not known to participate directly in any nucleophilic substitution mechanisms that impact the actual glycosyl transfer step. Read More

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http://dx.doi.org/10.1002/bit.27473DOI Listing

Moving from the Bench Towards a Large Scale, Industrial Platform Process for Adeno-Associated Viral Vector Purification.

Biotechnol Bioeng 2020 Jun 23. Epub 2020 Jun 23.

Regeneron Pharmaceuticals Inc., 777 Old Saw Mill River Road, Tarrytown, NY, 10591, USA.

In recent years, there has been a strong interest in the development and production of gene therapy products, especially those utilizing adeno-associated virus (AAV) particles. This is evident with the growing number of clinical successes and agency approvals for AAV therapeutics. Due to this increased investment in this technology, a need exists for scalable commercial production methods to ensure adequate product supply as research in AAV shifts from bench scale development to clinical production. Read More

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http://dx.doi.org/10.1002/bit.27472DOI Listing

Epidermal growth factor-immobilized surfaces for the selective expansion of neural progenitor cells derived from induced pluripotent stem cells.

Biotechnol Bioeng 2020 May 30. Epub 2020 May 30.

Department of Biomaterials, Graduate School of Biomedical and Health Sciences, Hiroshima University, Hiroshima, Japan.

Neural progenitor cells (NPCs) are considered to be a promising source for stem cell-based regenerative therapy for central nervous disorders. However, the widespread clinical application of NPCs requires another technology that permits the efficient production of pure NPCs in large quantities. In this study, culture substrates were designed by immobilizing epidermal growth factor (EGF) onto the substrate and evaluated for their feasibility of expanding NPCs obtained through the neurosphere culture of induced pluripotent stem (iPS) cells. Read More

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http://dx.doi.org/10.1002/bit.27445DOI Listing

Virus harvesting in perfusion culture: Choosing the right type of hollow fiber membrane.

Biotechnol Bioeng 2020 Jun 22. Epub 2020 Jun 22.

Bioprocess Engineering, Max Planck Institute for Dynamics of Complex Technical Systems, Magdeburg, Germany.

The use of bioreactors coupled to membrane-based perfusion systems enables very high cell and product concentrations in vaccine and viral vector manufacturing. Many virus particles, however, are not stable and either lose their infectivity or physically degrade resulting in significant product losses if not harvested continuously. Even hollow fiber membranes with a nominal pore size of 0. Read More

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http://dx.doi.org/10.1002/bit.27470DOI Listing

Bioprocess considerations for T-cell therapy: Investigating the impact of agitation, dissolved oxygen, and pH on T-cell expansion and differentiation.

Biotechnol Bioeng 2020 Jun 22. Epub 2020 Jun 22.

Department of Biochemical Engineering, The Advanced Centre for Biochemical Engineering, University College London, London, UK.

Adoptive T-cell therapy (ACT) has emerged as a promising new way to treat systemic cancers such as acute lymphoblastic leukemia. However, the robustness and reproducibility of the manufacturing process remains a challenge. Here, a single-use 24-well microbioreactor (micro-Matrix) was assessed for its use as a high-throughput screening tool to investigate the effect and the interaction of different shaking speeds, dissolved oxygen (DO), and pH levels on the growth and differentiation of primary T cells in a perfusion-mimic process. Read More

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http://dx.doi.org/10.1002/bit.27468DOI Listing

Bioprocess development for scalable production of cultivated meat.

Biotechnol Bioeng 2020 Jun 22. Epub 2020 Jun 22.

Department of Biosciences, School of Life and Health Sciences, Aston University, Aston Triangle, Birmingham, United Kingdom.

Traditional farm-based products based on livestock are one of the main contributors to greenhouse gas emissions. Cultivated meat is an alternative which mimics animal meat, being produced in a bioreactor under controlled conditions rather than through slaughtering of animals. The first step in the production of cultivated meat is the generation of sufficient reserves of starting cells. Read More

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http://dx.doi.org/10.1002/bit.27469DOI Listing

Biomimetic Surface Delivery of NGF and BDNF to Enhance Neurite Outgrowth.

Biotechnol Bioeng 2020 Jun 22. Epub 2020 Jun 22.

Department of Materials Science and Engineering, Sir Robert Hadfield Building, Mappin Street, The University of Sheffield, S1 3JD, United Kingdom.

Treatment for peripheral nerve injuries includes the use of autografts and nerve guide conduits. However, outcomes are limited, and full recovery is rarely achieved. The use of nerve scaffolds as a platform to surface immobilize neurotrophic factors and deliver locally is a promising approach to support neurite and nerve outgrowth after injury. Read More

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http://dx.doi.org/10.1002/bit.27466DOI Listing

Expanding the Chinese hamster ovary cell long non-coding RNA transcriptome using RNASeq.

Biotechnol Bioeng 2020 Jun 19. Epub 2020 Jun 19.

National Institute for Bioprocessing Research and Training, Fosters Avenue, Blackrock, Co. Dublin, Ireland.

Our ability to study Chinese hamster ovary (CHO) cell biology has been revolutionised over the last decade following the development of next generation sequencing technology and publication of reference DNA sequences for CHO cells and the Chinese hamster. RNA sequencing has not only enabled the association of transcript expression with bioreactor conditions and desirable bioprocess phenotypes but played a key role in the characterisation of protein coding and small non-coding RNAs. The annotation of long non-coding RNAs, and therefore our understanding of their role in CHO cell biology, has been limited to date. Read More

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http://dx.doi.org/10.1002/bit.27467DOI Listing

Dynamic flux balance analysis of biomass and lipid production by Antarctic thraustochytrid Oblongichytrium sp. RT2316-13.

Biotechnol Bioeng 2020 Jun 18. Epub 2020 Jun 18.

School of Engineering, Massey University, Palmerston North, New Zealand.

Production of biomass and lipids in batch cultures of the Antarctic thraustochytrid Oblongichytrium sp. RT2316-13, is reported. The microorganism proved capable of producing nearly 67% docosahexaenoic acid (DHA) and 15% eicosapentaenoic acid (EPA) in its total lipid fraction. Read More

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http://dx.doi.org/10.1002/bit.27463DOI Listing

Three-dimensional imaging and quantification of real-time cytosolic calcium oscillations in microglial cells cultured on electrospun matrices using laser scanning confocal microscopy.

Biotechnol Bioeng 2020 Jun 18. Epub 2020 Jun 18.

Department of Chemical Engineering, Indian Institute of Technology Hyderabad, Sangareddy, Telangana, India.

The development of a minimally invasive, robust, and inexpensive technique that permits real-time monitoring of cell responses on biomaterial scaffolds can improve the eventual outcomes of scaffold-based tissue engineering strategies. Towards establishing correlations between in situ biological activity and cell fate, we have developed a comprehensive workflow for real-time volumetric imaging of spatiotemporally varying cytosolic calcium oscillations in pure microglial cells cultured on electrospun meshes. Live HMC3 cells on randomly oriented electrospun fibers were stained with a fluorescent dye and imaged using a laser scanning confocal microscope. Read More

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http://dx.doi.org/10.1002/bit.27465DOI Listing

Spy chemistry-enabled protein directional immobilization and protein purification.

Biotechnol Bioeng 2020 Jun 16. Epub 2020 Jun 16.

School of Biology and Biological Engineering, South China University of Technology, Guangzhou, Guangdong, China.

Site-directed protein immobilization allows the homogeneous orientation of proteins with high retention of activity, which is advantageous for many applications. Here, we report a facile, specific, and efficient strategy based on the SpyTag-SpyCatcher chemistry. Two SpyTag-fused model proteins, that is, the monomeric red fluorescent protein (RFP) and the oligomeric glutaryl-7-aminocephalosporanic acid acylase, were easily immobilized onto a SpyCatcher-modified resin directly from cell lysates, with activity recoveries in the range of 85-91%. Read More

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http://dx.doi.org/10.1002/bit.27460DOI Listing
June 2020
4.126 Impact Factor

Alveolar mimics with periodic strain and its effect on the cell layer formation.

Biotechnol Bioeng 2020 Jun 15. Epub 2020 Jun 15.

Département de Chimie, Sorbonne Universités-UPMC Univ Paris 06, CNRS UMR 8640, Pasteur, École Normale Supérieure-PSL Research University, Paris, France.

We report on the development of a new model of alveolar air-tissue interface on a chip. The model consists of an array of suspended hexagonal monolayers of gelatin nanofibers supported by microframes and a microfluidic device for the patch integration. The suspended monolayers are deformed to a central displacement of 40-80 µm at the air-liquid interface by application of air pressure in the range of 200-1,000 Pa. Read More

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http://dx.doi.org/10.1002/bit.27458DOI Listing

Fabrication of a Biomimetic Spinal Cord Tissue Construct with Heterogenous Mechanical Properties using Intrascaffold Cell Assembly.

Biotechnol Bioeng 2020 Jun 15. Epub 2020 Jun 15.

Biomanufacturing Center, Department of Mechanical Engineering, Tsinghua University, Beijing, PRC.

In tissue engineering studies, scaffolds play very important role in offering both physical and chemical cues for cell growth and tissue regeneration. However, in some cases, tissue regeneration requires scaffolds with high mechanical properties (e.g. Read More

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http://dx.doi.org/10.1002/bit.27459DOI Listing

Simulated oxygen and glucose gradients as a prerequisite for predicting industrial scale performance a priori.

Biotechnol Bioeng 2020 Jun 12. Epub 2020 Jun 12.

Institute of Biochemical Engineering, University of Stuttgart, Stuttgart, Germany.

Transferring bioprocesses from lab to industrial scale without loss of performance is key for the successful implementation of novel production approaches. Because mixing and mass transfer is usually hampered in large scale, cells experience heterogeneities eventually causing deteriorated yields, that is, reduced titers, productivities, and sugar-to-product conversions. Accordingly, reliable and easy-to-implement tools for a priori prediction of large-scale performance based on dry and wet-lab tests are heavily needed. Read More

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http://dx.doi.org/10.1002/bit.27457DOI Listing

Pathway engineering of Escherichia coli for α-ketoglutaric acid production.

Biotechnol Bioeng 2020 Jun 12. Epub 2020 Jun 12.

State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.

α-Ketoglutaric acid (α-KG) is a multifunctional dicarboxylic acid in the tricarboxylic acid (TCA) cycle, but microbial engineering for α-KG production is not economically efficient, due to the intrinsic inefficiency of its biosynthetic pathway. In this study, pathway engineering was used to improve pathway efficiency for α-KG production in Escherichia coli. First, the TCA cycle was rewired for α-KG production starting from pyruvate, and the engineered strain E. Read More

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http://dx.doi.org/10.1002/bit.27456DOI Listing

Repurposing a bacterial prolidase for organophosphorus hydrolysis: Reshaped catalytic cavity switches substrate selectivity.

Biotechnol Bioeng 2020 Jun 9. Epub 2020 Jun 9.

CAS Key Laboratory of Tropical Marine Bio-resources and Ecology, Guangdong Key Laboratory of Marine Materia Medica, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou, China.

Enzyme promiscuity is critical to the acquisition of evolutionary plasticity in cells and can be recruited for high-value chemical synthesis or xenobiotic degradation. The molecular determinants of substrate ambiguity are essential to this activity; however, these details remain unknown. Here, we performed the directed evolution of a prolidase to enhance its initially weak paraoxonase activity. Read More

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http://dx.doi.org/10.1002/bit.27455DOI Listing

Vesicle transport and growth dynamics in Aspergillus niger: Microscale modeling of secretory vesicle flow and centerline extraction from confocal fluorescent data.

Biotechnol Bioeng 2020 Jun 8. Epub 2020 Jun 8.

Chair of Measurement and Control, Technische Universität Berlin, Berlin, Germany.

In this paper, we present a mathematical model to describe filamentous fungal growth based on intracellular secretory vesicles (SVs), which transport cell wall components to the hyphal tip. Vesicular transport inside elongating hyphae is modeled as an advection-diffusion-reaction equation with a moving boundary, transformed into fixed coordinates, and discretized using a high-order weighted essentially nonoscillatory discretization scheme. The model describes the production and the consumption of SVs with kinetic functions. Read More

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http://dx.doi.org/10.1002/bit.27452DOI Listing

Enhanced osteogenic differentiation of human mesenchymal stem cells by direct delivery of Cbfβ protein.

Biotechnol Bioeng 2020 Jun 8. Epub 2020 Jun 8.

Department of Medical Biomaterials Engineering, Kangwon National University, Chuncheon-si, Gangwon-do, Republic of Korea.

Core binding factor β (Cbfβ) is a non-DNA binding cofactor of Runx2 that potentiates DNA binding. Previously, it has been reported that Cbfβ plays an essential role in osteogenic differentiation and skeletal development by inhibition adipogenesis. Here, we delivered the recombinant Cbfβ protein into human mesenchymal stem cells (MSCs) and triggered osteogenic lineage commitment. Read More

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http://dx.doi.org/10.1002/bit.27453DOI Listing

Biomass soft sensor for a Pichia pastoris fed-batch process based on phase detection and hybrid modeling.

Biotechnol Bioeng 2020 Jun 8. Epub 2020 Jun 8.

Chair of Brewing and Beverage Technology, Technical University of Munich, Freising, Germany.

A common control strategy for production of recombinant proteins in Pichia pastoris using the alcohol oxidase 1 (AOX1) promotor is to separate the bioprocess into two main phases: biomass generation on glycerol and protein production via methanol induction. This study reports the establishment of a soft sensor for the prediction of biomass concentration that adapts automatically to these distinct phases. A hybrid approach combining mechanistic (carbon balance) and data-driven modeling (multiple linear regression) is used for this purpose. Read More

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http://dx.doi.org/10.1002/bit.27454DOI Listing

A mechanobiological mathematical model of liver metabolism.

Biotechnol Bioeng 2020 Jun 5. Epub 2020 Jun 5.

Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts.

The liver plays a complex role in metabolism and detoxification, and better tools are needed to understand its function and to develop liver-targeted therapies. In this study, we establish a mechanobiological model of liver transport and hepatocyte biology to elucidate the metabolism of urea and albumin, the production/detoxification of ammonia, and consumption of oxygen and nutrients. Since hepatocellular shear stress (SS) can influence the enzymatic activities of liver, the effect of SS on the urea and albumin synthesis are empirically modeled through the mechanotransduction mechanisms. Read More

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http://dx.doi.org/10.1002/bit.27451DOI Listing

Engineered citrate synthase improves citramalic acid generation in Escherichia coli.

Biotechnol Bioeng 2020 Jun 4. Epub 2020 Jun 4.

School of Chemical, Materials and Biomedical Engineering, University of Georgia, Athens, Georgia.

The microbial product citramalic acid (citramalate) serves as a five-carbon precursor for the chemical synthesis of methacrylic acid. This biochemical is synthesized in Escherichia coli directly by the condensation of pyruvate and acetyl-CoA via the enzyme citramalate synthase. The principal competing enzyme with citramalate synthase is citrate synthase, which mediates the condensation reaction of oxaloacetate and acetyl-CoA to form citrate and begin the tricarboxylic acid cycle. Read More

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http://dx.doi.org/10.1002/bit.27450DOI Listing

Semi-rational engineering of an amino acid racemase that is stabilized in aqueous/organic solvent mixtures.

Biotechnol Bioeng 2020 Jun 3. Epub 2020 Jun 3.

Department of Biosystems Science and Engineering, ETH Zurich, Basel, Switzerland.

Enzymes are industrially applied under increasingly diverse environmental conditions that are dictated by the efforts to optimize overall process efficiency. Engineering the operational stability of biocatalysts to enhance their half-lives under the desired process conditions is a widely applied strategy to reduce costs. Here, we present a simple method to enhance enzyme stability in the presence of monophasic aqueous/organic solvent mixtures based on the concept of strengthening the enzyme's surface hydrogen-bond network by exchanging surface-located amino acid residues for arginine. Read More

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http://dx.doi.org/10.1002/bit.27449DOI Listing

Exosomes derived from chemically induced human hepatic progenitors inhibit oxidative stress induced cell death.

Biotechnol Bioeng 2020 Jun 2. Epub 2020 Jun 2.

Center for Exosome & Bioparticulate Research, Hanyang University, Gyeonggi-do, Korea.

The emerging field of regenerative medicine has revealed that the exosome contributes to many aspects of development and disease through intercellular communication between donor and recipient cells. However, the biological functions of exosomes secreted from cells have remained largely unexplored. Here, we report that the human hepatic progenitor cells (CdHs)-derived exosome (EXO ) plays a crucial role in maintaining cell viability. Read More

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http://dx.doi.org/10.1002/bit.27447DOI Listing
June 2020
4.126 Impact Factor

Role of glycine 256 residue in improving the catalytic efficiency of mutant endoglucanase of family 5 glycoside hydrolase from Bacillus amyloliquefaciens SS35.

Biotechnol Bioeng 2020 Jun 2. Epub 2020 Jun 2.

Carbohydrate Enzyme Biotechnology Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati, Assam, India.

Wild-type, BaGH5-WT and mutant, BaGH5-UV2 (aspartate residue mutated to glycine), endoglucanases belonging to glycoside hydrolase family 5 (GH5), from wild-type, and UV2 mutant strain of Bacillus amyloliquefaciens SS35, respectively, were earlier cloned in pHTP0 cloning vector. In this study, genes encoding BaGH5-WT or BaGH5-UV2 were cloned into pET28a(+) expression-vector and expressed in Escherichia coli BL-21(DE3)pLysS cells. BaGH5-UV2 showed 10-fold (43. Read More

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http://dx.doi.org/10.1002/bit.27448DOI Listing

Engineering slit-like channels for studying the growth of epithelial tissues in 3D-confined spaces.

Biotechnol Bioeng 2020 Jun 2. Epub 2020 Jun 2.

University of Mons, Laboratory for Complex Fluids and Interfaces, Mechanobiology and Soft Matter Group, CIRMAP, Research Institute for Biosciences, Place du Parc, Mons, Belgium.

The development of epithelial lumens in ducts is essential to the functioning of various organs and in organogenesis. Ductal elongation requires the collective migration of cell cohorts in three-dimensional (3D) confined spaces, while maintaining their epithelial integrity. Epithelial lumens generally adopt circular morphologies, however abnormalities in complex physiological environments can lead to the narrowing of glandular spaces that adopt elongated and slit-like morphologies. Read More

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http://dx.doi.org/10.1002/bit.27446DOI Listing

Comprehensive characterization of tense and relaxed quaternary state glutaraldehyde polymerized bovine hemoglobin as a function of cross-link density.

Biotechnol Bioeng 2020 May 30. Epub 2020 May 30.

William G. Lowrie Department of Chemical and Biomolecular Engineering, The Ohio State University, Columbus, Ohio.

Previously, our lab developed high molecular weight (MW) tense (T) quaternary state glutaraldehyde polymerized bovine hemoglobins (PolybHbs) that exhibited reduced vasoactivity in several small animal models. In this study, we prepared PolybHb in the T and relaxed (R) quaternary state with ultrahigh MW (>500 kDa) with varying cross-link densities, and investigated the effect of MW on key biophysical properties (i.e. Read More

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http://dx.doi.org/10.1002/bit.27382DOI Listing

Improved two-stage protein expression and purification via autoinduction of both autolysis and auto DNA/RNA hydrolysis conferred by phage lysozyme and DNA/RNA endonuclease.

Biotechnol Bioeng 2020 May 28. Epub 2020 May 28.

Department of Biomedical Engineering, Duke University, Durham, North Carolina.

We report improved release of recombinant proteins in Escherichia coli, which relies on combined cellular autolysis and DNA/RNA autohydrolysis, conferred by the tightly controlled autoinduction of both phage lysozyme and the nonspecific DNA/RNA endonuclease from Serratia marcescens. Autoinduction occurs in a two-stage process wherein heterologous protein expression and autolysis enzymes are induced upon entry into stationary phase by phosphate depletion. Cytoplasmic lysozyme and periplasmic endonuclease are kept from inducing lysis until membrane integrity is disrupted. Read More

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http://dx.doi.org/10.1002/bit.27444DOI Listing

CRISPRi-mediated programming essential gene can as a Direct Enzymatic Performance Evaluation & Determination (DEPEND) system.

Biotechnol Bioeng 2020 May 27. Epub 2020 May 27.

Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan.

Harnessing enzyme expression for production of target chemicals is a critical and multifarious process, where screening of different genes by inspection of enzymatic activity plays an imperative role. Here, we conceived an idea to improve the time-consuming and labor-intensive process of enzyme screening. Controlling cell growth was achieved by the Cluster Regularly Interspaced Short Palindromic Repeat (CRISPRi) system with different single guide RNA targeting the essential gene can (CRISPRi::CA) that encodes a carbonic anhydrase for CO uptake. Read More

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http://dx.doi.org/10.1002/bit.27443DOI Listing

A predictive dynamic yeast model based on component, energy, and electron carrier balances.

Biotechnol Bioeng 2020 May 27. Epub 2020 May 27.

LGPM, CentraleSupélec, Université Paris-Saclay, Gif-sur-Yvette, France.

The present study describes a novel yeast model for the prediction of yeast fermentation. The proposed model considers the possible metabolic pathways of yeast. For each pathway, the time evolution of components, energy (ATP/ADP), and electron carriers (NAD /NADH) are expressed with limitation factors for all quantities consumed by each respective pathway. Read More

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http://dx.doi.org/10.1002/bit.27442DOI Listing

Crispr/Cas9-mediated cleavages facilitate homologous recombination during genetic engineering of a large chromosomal region.

Biotechnol Bioeng 2020 May 25. Epub 2020 May 25.

Department of Pharmaceutical Sciences, Washington State University College of Pharmacy, Spokane, Washington.

Homologous recombination over large genomic regions is difficult to achieve due to low efficiencies. Here, we report the successful engineering of a humanized mTert allele, hmTert, in the mouse genome by replacing an 18.1-kb genomic region around the mTert gene with a recombinant fragment of over 45. Read More

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http://dx.doi.org/10.1002/bit.27441DOI Listing

Scalable, two-stage, autoinduction of recombinant protein expression in E. coli utilizing phosphate depletion.

Biotechnol Bioeng 2020 May 22. Epub 2020 May 22.

Department of Biomedical Engineering, Duke University, Durham, North Carolina.

We report the scalable production of recombinant proteins in Escherichia coli, reliant on tightly controlled autoinduction, triggered by phosphate depletion in the stationary phase. The method, reliant on engineered strains and plasmids, enables improved protein expression across scales. Expression levels using this approach have reached as high as 55% of the total cellular protein. Read More

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http://dx.doi.org/10.1002/bit.27440DOI Listing

Development of orthogonal T7 expression system in Klebsiella pneumoniae.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Beijing Key Laboratory of Bioprocess, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing, China.

Most expression systems are tailored for model organisms rather than nonmodel organisms. However, heterologous gene expression in model organisms constrains the innate advantages of original strain carrying gene of interest. In this study, T7 expression system was developed in nonmodel bacterium Klebsiella pneumoniae for production of chemicals. Read More

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http://dx.doi.org/10.1002/bit.27434DOI Listing

Enhancing plasmid transformation efficiency and enabling CRISPR-Cas9/Cpf1-based genome editing in Clostridium tyrobutyricum.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Department of Biosystems Engineering, Auburn University, Auburn, Alabama.

Clostridium tyrobutyricum ATCC 25755 is known as a natural hyper-butyrate producer with great potentials as an excellent platform to be engineered for valuable biochemical production from renewable resources. However, limited transformation efficiency and the lack of genetic manipulation tools have hampered the broader applications of this micro-organism. In this study, the effects of Type I restriction-modification system and native plasmid on conjugation efficiency of C. Read More

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http://dx.doi.org/10.1002/bit.27435DOI Listing

Impacts on product quality attributes of monoclonal antibodies produced in CHO cell bioreactor cultures during intentional mycoplasma contamination events.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Division of Biotechnology Review and Research II, U.S. Food and Drug Administration, Center for Drug Evaluation and Research, Office of Pharmaceutical Quality, Office of Biotechnology Products, Silver Spring, Maryland.

A mycoplasma contamination event in a biomanufacturing facility can result in costly cleanups and potential drug shortages. Mycoplasma may survive in mammalian cell cultures with only subtle changes to the culture and penetrate the standard 0.2-µm filters used in the clarification of harvested cell culture fluid. Read More

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http://dx.doi.org/10.1002/bit.27436DOI Listing

Microbial production of 4-amino-1-butanol, a four-carbon amino alcohol.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Metabolic and Biomolecular Engineering National Research Laboratory, Systems Metabolic Engineering and Systems Healthcare (SMESH) Cross-Generation Collaborative Laboratory, Department of Chemical and Biomolecular Engineering (BK21 Plus Program), Institute for the BioCentury, Korea Advanced Institute of Science and Technology (KAIST), Daejeon, Republic of Korea.

4-Amino-1-butanol (4AB) serves as an important intermediate compound for drugs and a precursor of biodegradable polymers used for gene delivery. Here, we report for the first time the fermentative production of 4AB from glucose by metabolically engineered Corynebacterium glutamicum harboring a newly designed pathway comprising a putrescine (PUT) aminotransferase (encoded by ygjG) and an aldehyde dehydrogenase (encoded by yqhD) from Escherichia coli, which convert PUT to 4AB. Application of several metabolic engineering strategies such as fine-tuning the expression levels of ygjG and yqhD, eliminating competing pathways, and optimizing culture condition further improved 4AB production. Read More

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http://dx.doi.org/10.1002/bit.27438DOI Listing

Overexpression of the mitochondrial pyruvate carrier reduces lactate production and increases recombinant protein productivity in CHO cells.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Instituto de Biotecnología, Universidad Nacional Autónoma de México, Morelos, Mexico.

Chinese hamster ovary (CHO) cells are characterized by a low glucose catabolic efficiency, resulting in undesirable lactate production. Here, it is hypothesized that such low efficiency is determined by the transport of pyruvate into the mitochondria. The mitochondrial pyruvate carrier (MPC), responsible for introducing pyruvate into the mitochondria, is formed by two subunits, MPC1 and MPC2. Read More

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http://dx.doi.org/10.1002/bit.27439DOI Listing

Hybrid-EKF: Hybrid model coupled with extended Kalman filter for real-time monitoring and control of mammalian cell culture.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

DataHow AG, Zurich, Switzerland.

In a decade when Industry 4.0 and quality by design are major technology drivers of biopharma, automated and adaptive process monitoring and control are inevitable requirements and model-based solutions are key enablers in fulfilling these goals. Despite strong advancement in process digitalization, in most cases, the generated datasets are not sufficient for relying on purely data-driven methods, whereas the underlying complex bioprocesses are still not completely understood. Read More

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http://dx.doi.org/10.1002/bit.27437DOI Listing

Construction of an engineered biocatalyst system for the production of medium-chain α,ω-dicarboxylic acids from medium-chain ω-hydroxycarboxylic acids.

Biotechnol Bioeng 2020 May 21. Epub 2020 May 21.

Department of Bioscience and Biotechnology, Konkuk University, Seoul, Republic of Korea.

Medium-chain α,ω-dicarboxylic acids produced from renewable long-chain fatty acids are valuable as precursors in the chemical industry. However, they are difficult to produce biologically at high concentrations. Although improved biocatalyst systems consisting of engineering of Baeyer-Villiger monooxygenases are used in the production of ω-hydroxycarboxylic acids from long-chain fatty acids, the engineering of biocatalysts involved in the production of α,ω-dicarboxylic acids from ω-hydroxycarboxylic acids has been rarely attempted. Read More

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http://dx.doi.org/10.1002/bit.27433DOI Listing

Chromosome-scale scaffolds for the Chinese hamster reference genome assembly to facilitate the study of the CHO epigenome.

Biotechnol Bioeng 2020 May 15. Epub 2020 May 15.

Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, Delaware.

The Chinese hamster genome serves as a reference genome for the study of Chinese hamster ovary (CHO) cells, the preferred host system for biopharmaceutical production. Recent re-sequencing of the Chinese hamster genome resulted in the RefSeq PICR meta-assembly, a set of highly accurate scaffolds that filled over 95% of the gaps in previous assembly versions. However, these scaffolds did not reach chromosome-scale due to the absence of long-range scaffolding information during the meta-assembly process. Read More

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http://dx.doi.org/10.1002/bit.27432DOI Listing
May 2020
4.126 Impact Factor

Mucus blocks probiotics but increases penetration of motile pathogens and induces TNF-α and IL-8 secretion.

Biotechnol Bioeng 2020 May 12. Epub 2020 May 12.

Department of Chemical Engineering, University of Massachusetts Amherst, Amherst, Massachusetts.

The mucosal barrier in combination with innate immune system are the first line of defense against luminal bacteria at the intestinal mucosa. Dysfunction of the mucus layer and bacterial infiltration are linked to tissue inflammation and disease. To study host-bacterial interactions at the mucosal interface, we created an experimental model that contains luminal space, a mucus layer, an epithelial layer, and suspended immune cells. Read More

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http://dx.doi.org/10.1002/bit.27383DOI Listing

Label-free, chronological and selective detection of aggregation and fibrillization of amyloid β protein in serum by microcantilever sensor immobilizing cholesterol-incorporated liposome.

Biotechnol Bioeng 2020 May 12. Epub 2020 May 12.

Graduate School of Science and Technology, Kyoto Institute of Technology, Matsugasaki, Sakyo-ku, Kyoto, Japan.

To facilitate the early diagnosis of Alzheimer's disease and mild cognitive impairment patients, we developed a cantilever-based microsensor that immobilized liposomes of various phospholipids to detect a trace amount of amyloid β (Aβ) protein, and investigated its aggregation and fibrillization on model cell membranes in human serum. Three species of liposomes composed of different phospholipids of 1,2-dipalmtoyl-sn-glycero-3-phosphocholine (DPPC), DPPC/phosphatidyl ethanolamine and 1,2-dipalmitoyl-sn-glycero-3-phosphorylglycerol having varied hydrophilic groups were applied, which showed different chronological interactions with Aβ(1-40) protein and varied sensitivities of the cantilever sensor, depending on their specific electrostatic charged conditions, hydrophilicity, and membrane fluidity. 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) having short hydrophobic carbon chains confirmed to show a large interaction with Aβ(1-40) and a high sensitivity. Read More

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http://dx.doi.org/10.1002/bit.27380DOI Listing